Rodean Crescent Basement

This project involved a residential basement construction in central London. The basement was to be constructed underneath an existing dwelling and to extend into the garden at the rear of the property. A double storey basement was required to facilitate a swimming pool construction and the associated internal structure. The architects required the internal space to be optimised which meant the basement was constructed tight to the site boundaries and construction activities were significantly constrained.

Scope of Work:

Gavin and Doherty Geosolutions Ltd. (GDG) was requested by Structure UK Ltd. to undertake the design of the primary basement structure including the secant pile walls and the internal bearing piles for the basement construction at a property on 25 Roedean Crescent, Richmond upon Thames. This was constructed using the top-down approach.

The two storey basement construction involved the installation of a secant pile wall to retain up to approximately 8 m of soil at the maximum excavation depth. These walls were required to support significant vertical loads from the structure in addition to the retained soil pressures. The internal bearing pile design had dual functions to resist superstructure loads in some areas of the excavation and tension loads in other parts. The temporary works involved internal plunge pile design, and capping beam stiffeners around the excavation access ope.

The pile analysis for this project was undertaken using a combination of software models developed in FREW, Lpile, and analytical in-house programs. The output of these models included ground movements and stresses. This aspect of the project was particularly important due to the close proximity of neighbouring properties and the sensitivity of these structures to ground movements.

Construction drawings were provided for the basement layout, sections through the basement walls and detailed reinforcing design of the pile cages.